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High‐dielectric thin films are considered as future dielectric for Si based advanced integrated circuit technology and also for the development of organic thin film transistors and micro sensors. The conventional dielectric SiO₂ is grown by thermal oxidation of silicon whereas the HfO₂ films are grown by both physical and chemical methods. Depending on film deposition technique, the film and interface characteristics are affected. The purpose of this paper is to investigate the effect of thermal annealing in oxygen and nitrogen ambient on the electrical properties of HfO₂‐based metal oxide semiconductor (MOS) capacitor and evaluate thermal stability of the characteristics.

HfO₂ films are deposited by rf sputtering and Al‐HfO₂‐Si MOS capacitor fabricated. The electrical I‐V and C‐V characteristics are measured and the effect of temperature in the range of 25‐200°C is evaluated for films annealed in oxygen and nitrogen.

It is found that thermal annealing in nitrogen reduces oxide trap density and improves the temperature stability compared to the film annealed in oxygen for MOS devices. From the conductance characteristics D_it oxide trap density in the film is estimated to be 2.1×10¹¹/cm² for nitrogen and 3.23×10¹¹/cm² for oxygen, which indicates the role of nitrogen in reducing oxide traps. The thermal activation energy of electron traps is found to be about 0.19 eV for nitrogen and 0.58 eV for oxygen annealed films in the temperature range of 25‐150°C.

The paper examines and compares the role and effect of thermal annealing in nitrogen ambient and oxygen ambient on the electrical properties of sputtered HfO₂ thin film for improved MOS device reliability.

HfO₂ has emerged as the most promising high k dielectric for an alternative gate material. As‐deposited HfO₂ thin films have large number of defects resulting in increased oxide charge and leakage current. Film deposition condition plays an important role. This paper investigates the effect of sputtering voltage, bias sputtering and post deposition thermal annealing.

The microstructure of the film is examined by AFM. The I‐V and C‐V characteristics is evaluated from Al‐HfO₂‐Si capacitor structures and the effect of processing conditions is studied. The experimental results are reported and discussed for improving film properties.

It is found that applying substrate bias during film deposition improves interface and reduce leakage current and oxide charges.

The paper studies the effect of deposition voltage and thermal annealing on thin film deposition of HfO₂ by rf sputtering.

The purpose of this study is to empirically estimate the impact of a government microcredit program on the handloom weavers to promote small and medium enterprises (SMEs) in Bangladesh.

The data were collected from 311 handloom weavers from the Sirajganj District of Bangladesh from July to December 2015 using a multistage sampling technique. The analysis was conducted using a two-stage least squares regression model incorporating instrumental variables to control for the probable endogeneity problem associated with the study.

This study finds that government microcredit had no significant impact on borrowers' investment in their business, whereas credit received from multiple sources other than government credit had a significant negative impact. Additionally, literacy level, household assets and the number of operational handloom units positively affected investment, while the number of non-operational handloom units and distance negatively affected the investment.

This study's findings are more specific for the selected case and may not be generalizable to all kinds of SMEs.

The policy implications are targeted at increasing loan size based on the number of operational handloom units to improve the performance of government and other microcredit programs to facilitate the growth of SMEs in Bangladesh.

This study specifically focuses on estimating the financial performance of government microcredit programs for SME development within the handloom industry, which has not been sufficiently explored in the literature.

This study aims to investigate the effect of different pore diameter and pore length on corrosion properties of anodic aluminum oxide (AAO) film.

AAO layer was produced by two-step anodization aluminum in oxalic acid. The surface morphology was investigated using field emission scanning electron microscopy. The pore diameters were ranging from 25 ± 5 to 65 ± 5 nm and the pore length ranging from 5 to 17 µm. The corrosion properties of the AAO films was analyzed by potentiodynamic polarization and electrochemical impedance spectroscopy tests. Corrosion properties and morphology of the anodic films depending on anodization times and pore expansion times were evaluated.

All highlights of this work can be summarized with the following specified below: more treatment with the protective barrier layer of the solution as the pore diameter increases depends on the morphology of the nanotube structured AAO layer. The excellent corrosion resistance renders AAO films without pore expansion very promising. The oxide layer thickness does not affect the corrosion resistance. The better corrosion resistance of AAO films at low pore length can be ascribed to the barrier layer thickness and the more homogeneous structure. The presence of defects for the higher pore length decreases its corrosion resistance.

The AAO films were fabricated by a two-step anodization method in oxalic acid. The anodization times and pore expansion times affect the corrosion performance. The AAO film without pore expansion has good corrosion resistance. The corrosion resistance decreases as the pore length increases.

The microwave properties of microstripline at S‐band and X‐band and ?/2 rejection filter with midband rejection at 3 GHz fabricated by thick film technology are studied. The effect of an overcoat of Ag thin film of thickness 2 µm deposited by ion plating and electroless plating on Ag and Pd‐Ag thick film circuits is reported. There is a drastic improvement in the performance of the thick film circuits after overcoating. This is attributed to the superior edge definition whereby losses are reduced. As the edge is smoother, especially at the coupling area of the filter, there is tighter coupling, thus increasing the Q of the filter. The overcoat may also reduce the large open areas of the thick film, giving a smoother upper surface finish. This type of metallic overcoat, i.e., hybrid of thick and thin film, may reduce the need for costly and time‐consuming functional trimming and expensive thick film materials.

Critical processing steps of COB manufacturing, as implemented at Epitek, are reported. They include testing of incoming boards, cleaning, bonding parameters, bonding defects and statistical process control.

Contemporary literature reveals that, to date, the poultry livestock sector has not received sufficient research attention. This particular industry suffers from unstructured supply chain practices, lack of awareness of the implications of the sustainability concept and failure to recycle poultry wastes. The current research thus attempts to develop an integrated supply chain model in the context of poultry industry in Bangladesh. The study considers both sustainability and supply chain issues in order to incorporate them in the poultry supply chain. By placing the forward and reverse supply chains in a single framework, existing problems can be resolved to gain economic, social and environmental benefits, which will be more sustainable than the present practices.

The theoretical underpinning of this research is ‘sustainability’ and the ‘supply chain processes’ in order to examine possible improvements in the poultry production process along with waste management. The research adopts the positivist paradigm and ‘design science’ methods with the support of system dynamics (SD) and the case study methods. Initially, a mental model is developed followed by the causal loop diagram based on in-depth interviews, focus group discussions and observation techniques. The causal model helps to understand the linkages between the associated variables for each issue. Finally, the causal loop diagram is transformed into a stock and flow (quantitative) model, which is a prerequisite for SD-based simulation modelling. A decision support system (DSS) is then developed to analyse the complex decision-making process along the supply chains.

The findings reveal that integration of the supply chain can bring economic, social and environmental sustainability along with a structured production process. It is also observed that the poultry industry can apply the model outcomes in the real-life practices with minor adjustments. This present research has both theoretical and practical implications. The proposed model’s unique characteristics in mitigating the existing problems are supported by the sustainability and supply chain theories. As for practical implications, the poultry industry in Bangladesh can follow the proposed supply chain structure (as par the research model) and test various policies via simulation prior to its application. Positive outcomes of the simulation study may provide enough confidence to implement the desired changes within the industry and their supply chain networks.

Effective cooling is one of the challenges for photovoltaic thermal (PVT) systems to maintain the PV operating temperature. One of the best ways to enhance rate of heat transfer of the PVT system is using advanced working fluids such as nanofluids. The purpose of this research is to develop a numerical model for designing different form of thermal collector systems with different materials. It is concluded that PVT system operated by nanofluid is more effective than water-based PVT system.

In this research, a three-dimensional numerical model of PVT with new baffle-based thermal collector system has been developed and solved using finite element method-based COMSOL Multyphysics software. Water-based different nanofluids (Ag, Cu, Al, etc.), various solid volume fractions up to 3 per cent and variation of inlet temperature (20-40°C) have been applied to obtain high thermal efficiency of this system.

The numerical results show that increasing solid volume fraction increases the thermal performance of PVT system operated by nanofluids, and optimum solid concentration is 2 per cent. The thermal efficiency is enhanced approximately by 7.49, 7.08 and 4.97 per cent for PVT system operated by water/Ag, water/Cu and water/Al nanofluids, respectively, compared to water. The extracted thermal energy from the PVT system decreases by 53.13, 52.69, 42.37 and 38.99 W for water, water/Al, water/Cu and water/Ag nanofluids, respectively, due to each 1°C increase in inlet temperature. The heat transfer rate from heat exchanger to cooling fluid enhances by about 18.43, 27.45 and 31.37 per cent for the PVT system operated by water/Al, water/Cu, water/Ag, respectively, compared to water.

This study is original and is not being considered for publication elsewhere. This is also not currently under review with any other journal.

The global spread of the COVID-19 pandemic resulted in the complete lockdown of almost every part of the world, including all educational institutions, resulting in the prompt implementation of online education to facilitate the students to carry on their learning. These conditions made the researchers study the experiences of online education among students and teachers. The influences of online teaching-learning during the COVID-19 pandemic undoubtedly offered numerous opportunities besides raising some challenges which impacted the overall psychology of students and teachers. So, this paper aims to conduct a systematic review of the research papers focussing on opportunities, challenges and psychological impacts raised due to the sudden shift to online education among students and teachers during the COVID-19 pandemic.

To conduct this systematic review, 19 articles published between July 2020 and May 2021 were considered and reported by following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA).

It was found that online education influenced the interests and experiences of the students and teachers and has immensely impacted their overall psychology. So, for the effective implementation of online and blended education, psychological well-being of students and teachers should be taken care of with properly designed instructions, adequate infrastructure or resources and satisfactory technological skills.

In the present study, the students were not categorised according to their subjects or streams, i.e. science, commerce, humanities, medical, dental, postgraduate or undergraduate. All the students were categorised into two categories only: (1) college students and (2) school students. And also, teachers were not categorised and were presented as a whole, as school, college or university teachers.

The current research identified the abrupt implementation of online education during the COVID-19 pandemic, which raised various challenges and psychological impacts among students and teachers besides offering them many opportunities in times of crisis.

Students and teachers constitute the educational community of society. They should get ample opportunities to develop skills for online education; challenges faced during online education should be identified and tackled, and the issues concerning the psychological well-being during online education for both teachers and students should be addressed to achieve sustained development of online education–blended learning environments.

The paper is the original research work based on the systematic review and concludes with suggestions for the future of online and blended pedagogy while taking care of the psychological needs of students and teachers in online and blended learning environments.

This study aims to investigate the impact of risk committee characteristics on the risk disclosure of banking institutions in an emerging economy, Pakistan.

The data are collected through a manual content analysis of 21 banks regulated by the State Bank of Pakistan over the period 2011–2020. The study utilizes the generalized least square (GLS) regression model as the method of analysis.

The study finds that risk committee size is positively associated with risk disclosure, which is in line with agency theory. However, risk committee independence and risk committee gender diversity are negatively associated with risk disclosure. This contradicts the theoretical perspective and is explained by the weak regulatory framework of Pakistan.

This study was carried out in a single research setting, which limits the generalizability of its findings to other developed and emerging economies.

The results provide valuable insights for regulators by identifying the attributes that require regulatory focus to strengthen risk committees and enhance risk disclosure practices within the banking sector of Pakistan. The findings highlight the effectiveness of the risk committee size, call for fully independent risk committees and encourage greater representation of women in these committees.

This study contributes to the corporate governance literature by empirically examining the risk committee characteristics and their impact on the risk disclosure of banks in an emerging economy. Moreover, this study contributes to theory by utilizing upper echelon theory in addition to agency theory as the motivation for the study.